Deodorizer sheet material

ABSTRACT

Shoe inserts are produced comprising a sole-shaped sheet or the like of foamed latex impregnated with activated charcoal. When such a shaped sheet is used as a shoe insert or insole it is found to substantially reduce or even eliminate foot odors frequently associated with perspiring feet.

United States Patent 1191 Lapidus 1 1 DEODORIZER SHEET MATERIAL [751lnventor: Herbert Lapidus, Ridgefield, Conn.

[73] Assignee: Combe Incorporated, White Plains,

[22] Filed: Jan. 26, 1973 [211 Appl. No.: 326,757

FOREIGN PATENTS OR APPLICATIONS 728,075 4/1955 Great Britain 36/441,937,373 1/1970 Germany 36/43 Primary Examiner-Alfred R. GuestAttorney, Agent, or Firm-Johnson, Dienner, Emrich, Verbeck & Wagner 5 7]ABSTRACT Shoe inserts are produced comprising a sole-shaped sheet or thelike of foamed latex impregnated with activated charcoal. When such ashaped sheet is used as a shoe insert or insole it is foundto-substantially reduce or even eliminate. foot odors frequentlyassociated with perspiring feet.

6 Claims, No Drawings DEODORIZER SHEET MATERIAL BACKGROUND OF THEINVENTION Activated charcoal has long been used as a filter aid withboth liquids and gases for the purpose of clarifying liquids anddeodorizing liquids and gases.

In recent times it has been proposed as for example in BritishSpecification No. 1,270,809 to incorporate activated charcoal into afibre web or mat, the web or mat being supported by a backing materialsuch as cloth obtained from natural sources as cotton, or formed of asynthetic such as nylon, and shaped so that the resulting web fits intoand covers the inner sole of a shoe. It has also been proposed to attacha layer or coating of a foam material such as polyurethane foam to sucha web for the purpose of providing increased strength and springiness.

SUMMARY OF THE INVENTION My invention is directed to a unique shoeinsert, or insole, which effectively and economically minimizes odorswhich are often associated with feet and which occur in conjunction withor as a result of perspiration.

' In general, my shoe insert comprises a foamed material,

and spread uniformly into a web of cloth or the like,

and then passed under a doctor blade to produce a desired thickness. Theresulting product is then heat processed in order to produce a latexfoam which is bonded to the web.

The resulting latex-foam sheets, containing charcoal dispersedtherethrough, are then cut into such sizes as are appropriate forfitting comfortably into shoes, male or female. In use the insole isinserted into the shoe with the impregnated latex facing downward in theshoe to thereby permit contact of the web or backing material with thefoot, and with the sock covering it.

The especially excellent effectiveness of my shoe insert seems to resultfrom the circulation of air and vapors through and around the highlyabsorbable carbon particles, which occurs when the shoe containing suchinsert is worn.

DESCRIPTION OF THE PREFERRED EMBODIMENT So that my invention may befully understood I shall hereinafter describe a specific exampleillustrating the practice of my invention. This illustration is for thatpurpose only, and is not intended to either limit the scope of theinvention or of the claims appended hereto.

EXAMPLE I Ingredients Dry Weight GR-S Latex 100.0 Ibs. Sulfur 1.5 lbs.Zinc Oxide 4.0 5.0 lbs. Surfactant 9.0 lbs. Filler 100.0 lbs.

EXAMPLE I-Continued Ingredients Dry Weight Activated Charcoal 25.0 32.0lbs. Antioxidant 1.2 lbs. Accelerator 2.5 lbs.

The GR-S latex, a synthetic cold-type styrenebutodiene manufactured bythe Goodyear Company of Akron, Ohio, is used in the form of an aqueousslurry (143.0 lbs). And the activated charcoal, available under thetradename Nu-Char, is also used in the form of an aqueous slurry (150.0lbs.).

The procedure used is as follows: The latex slurry is weighed out into asuitable mixing vessel and there is then added 9.0 lbs. of thesurfactant, dioctyl-sodiumsulfo-succinate, available from the AmericanCyanamid Company of New York, under the trade name of Aerosol O T. Thereis then added 2.5 lbs. of potassium persulfate as the accelerator,followed by additions of 1.5 lbs. of rubber makers grade sulfur, 4.0 to5.0 lbs. of zinc oxide (American Process) and 1.2 lbs of dioctylphospite antioxidant.

Silica flour filler (100.0 lbs.) is then added, followed by addition ofthe activated charcoal aqueous slurry (143. lbs. of which is Nu-Char).

If it is desired to increase the viscosity of the foregoing mix, asuitable thickener, e.g., Methocel may be added.

The above components are then mixed to form a homogenous mass, and isthen fed into a hopper, thence into a homogenizer, preferably an Oaksmixer, which is a rotor stator type homogenizer. Preferable two mixersare used in series. At the first mixer (called a prefrother) air isinjected to control the pour density of the product. The base weight ofthe finished controlled by regulation of this air.

The material is then pumped into the second mixer, also a homogenizer,where the froth is refined, controlling the cell structure size.

After the mix leaves the second mixer and onto a flat surface (belt ortable) covered with a layer of fabric which serves as a backing for thefinished insert the thickness of the flow is controlled by a doctorblade set to give a finished foam guage of /1000 inch.

Instead of applying the mix onto a flat survace covered with a layer offabric, as described above, the latex mix may be applied to a transferpaper instead. In other words, my sheet material can be produced with orwithout a fabric laminate.

Cup weights are taken after the mix leaves the second mixer; cup weightsbetween and grams are acceptable, 87 gramsbeing preferred. The tareweight (cup) is 24 grams.

The resulting material is then cured and dried in a forced hot air ovenat temperatures ranging from 310 F to 350 F, with approximately 3minutes of dwell time.

It will be understood, of course, by those skilled in the art thatvariations in the exact amounts and precise kinds of ingredients used inproducing my charcoalloaded latex foam are possible. Thusthe levels offinely ground activated charcoal used may be varied rather widely, forexample 35 percent or higher, by weight of the chemical mix producingthe latex foam (dry basis) may be used, limited of course by thedifficulty of inproduct is v corporation into the latex mix, economicconsiderations, appearance and the like..

And though one specific latex foam formulation has been set forth in theforegoing example, those persons skilled in the art will understand thatother foam formulations may be used, preferably those which can beprocessed to form an open-celled foam which breathes and allows for thepassage of air through its interstitial spaces.

While it is presently preferred that the open-celled foam in sheet formcomprising my invention be produced using latex, it is alsocontemplated, and is within the broad concept of my invention, thatother opencelled foams may be used, such as polyurethane foams and vinylchloride plastisol foams, especially where a slightly more rigid productis desired.

I claim:

1. A shoe insert for absorbing odors resulting from perspiring feetcomprising a cured sheet of opencelled foam, at least one side of thesheet having a relatively smooth skin formed during curing which isimpervious to passage of charcoal particles, said foam containinghomogeneously distributed through the solid part thereof finely dividedactivated charcoal particles in an amount effective to absorb odors whensaid sheet is subjected to contact with foot perspiration and to passageof odor-filled air through interstitial spaces within said foam, saidcharcoal particles having been incorporated prior to frothing and curingof said foam.

2. The article of claim 1 wherein the charcoal is present in the amountof about l0.2 to 35 percent.

3. The article of claim 1 wherein the other side has a backing layer ofa material which is pervious to passage of air, at least the outersurface of said layer being free of finely divided activated charcoal.

4. The. product of claim 1 wherein said foam is formed of latex.

5. The product of claim 2 wherein said material is a textile.

6. The product of claim 1 wherein said foam is selected from the groupconsisting of latex foams, polyurethane foams, and vinyl chlorideplastisol foams.

1. A SHOE INSERT FOR ABSORBING ODORS RESULTING FROM PERSPIRING FEETCOMPRISING A CURED SHEET OF OPENCELLED FOAM, AT LEAST ONE SIDE OF THESHEET HAVING A RELATIVELY SMOOTH SKIN FORMED DURING CURING WHICH ISIMPERVIOUS TO PASSAGE OF CHARCOAL PARTICLES, SAID FOAM CONTAININGHOMOGENEOUSLY DISTRIBUTED THROUGH THE SOLID PART THEREOF FINELY DIVIDEDACTIVATED CHARCOAL PARTICLES IN AN AMOUNT EFFECTIVE TO ABSORB ODORS WHENSAID SHEET IS SUBJECTED TO CONTACT WITH FOOT PERSPIRATION AND TO PASSAGEOF ODOR-FILLED AIR THROUGH INTERSTITIAL SPACES WITHIN SAID FOAM, SAIDCHARCOAL PARTICLES HAVING BEEN INCORPORATED PRIOR TO FROTHING AND CURINGOF SAID FOAM.
 2. The article of claim 1 wherein the charcoal is presentin the amount of about 10.2 to 35 percent.
 3. The article of claim 1wherein the other side has a backing layer of a material which ispervious to passage of air, at least the outer surface of said layerbeing free of finely divided activated charcoal.
 4. The product of claim1 wherein said foam is formed of latex.
 5. The product of claim 2wherein said material is a textile.
 6. The product of claim 1 whereinsaid foam is selected from the group consisting of latex foams,polyurethane foams, and vinyl chloride plastisol foams.